"The blood needed to be detailed and nuanced in the way it behaved, but also seem elegant and simple as a visual form," explains Andrew Romatz, CG Supervisor. "Scale would vary from tiny objects to epic cityscapes, but all had to feel consistent, and be technically achievable."

A team of artists working for a month to create the effect, using RealFlow to form phantom sculptures with fluid flowing around the shapes of models which were invisible.

"We wanted to be able to control the fluid behavior in a specific way, and still have the sim feel natural," says Romatz. “If the job requires any realistic fluid behavior, we turn to RealFlow first."

The team used directable velocity and developed custom fields to get the fluids to flow the way they needed them to. They remeshed multiple sims together and played with the world space scale to cheat speed.

Realflow was central to making the fluid blood look natural

"We got some bubbles in our final meshes which we ended up needing to paint out in compositing," he adds. “We needed to use 2D textures for the mesh but the UVs didn't give us enough control to do what we wanted so we had to animate 3D texture projections in Maya to give the appearance that the textures we're flowing with the liquid."

RealFlow was integrated seamlessly into A52's pipeline. “We render all of our work in VRay, so meshes are brought in as Alembic caches, and we didn't have any problems rendering out the meshes for this project at all," says Romatz.

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